The paper considers three basic schemes of roof failure above the face bottom of long-wall during mining operations covering the whole diversity of mechanisms of support-roof interaction. The relationships are given for the determination of required rated resistance of the powered support with reference to the schemes of roof failure.
The paper considers three basic schemes of roof failure above the face bottom of long-wall during mining operations covering the whole diversity of mechanisms of support-roof interaction. The model of interaction between the powered support and heavy roof is given as well as the calculated scheme for the determination of necessary rated resistance of roof.
The minable seam «Verkhny» within the Barentsburg coal deposit is geodynamically hazardous, its geodynamic phenomena manifest itself in the form of proper rock bursts, shocks in the marginal zones and dynamic faults of ground. Due to rockburst-hazardous situation the application of the areal relief of rock mass with transition to technological variants of mining with leaving the extended rib pillars at the boundary with the mined-out space, with their cutting by drivage of additional working is applied. Consideration is given to the recommended variants of pillar leaving with the data of their assignment and applicability to geological-and-mining conditions of mine field sections. Description is given to the calculation of pillar sizes and parameters used for their calculations. Some examples are given of pillar leaving at different sections of mine field with geometrical parameters as well as the information is given on the seam extraction with prospecting routes (paths) with leaving the support rib and barrier pillars. The leaving of safety support and barrier pillars with substantiation of their sizes is recommended as the method for providing the safe condition of mining the «Verkhny» coal seam
Within the bearing pressure zone in the working ’ s roof an increase of fracturing of rocks, decrease of their strength and stability, an increase of the working’s width take place in consequence of coal splitting in banks. All this leads to the increase of vault height of natural rock equilibrium as compared with the workings being driven in rock mass.
